The way I see it you should read "The Australian Connection", because it's an exciting and short story, which is about a kid, that lives and grown up with one parent. This book is the right one for people, who want to know how a life also can be without parents. Of course if you like situation with romance and adventure, it's a good one
for you too.
It's not difficult to understand, where you don't need a dictionary for looking up single words. At the end of the book there are some pages with the important vocabulary, which can help you to understand the story.
In my opinion, if you read this book, you will improve your speaking and understanding. This book will can maybe persuade (überzeugen) you to read English books. Of course you will learn new vocabulary and possibly in the future you can use your English language better. For me it was a good way to pick up new experience. I think it's not mistake, if you will read "The Australian Connection". Enjoy reading it!